There is a persistent demand for devices capable of storing more energy (Wh/l or Wh/kg) than today's premier rechargeable Li-ion batteries. One increasingly sought after route to meeting this demand is to utilize divalent magnesium ion (Mg2+), rather than the monovalent cation lithium (Li+) because magnesium enables nearly twice as much charge to be transferred, per weight or volume, as Li+ thus enabling high energy density. Furthermore the abundance of Mg metal and readily available compounds containing Mg will enable significant cost reduction relative to Li-ion batteries. Enabling a practical rechargeable Mg battery with an Mg metal anode requires electrolytes composed of strong Lewis basic organo-Mg compounds (i.e., Grignards), often complexed with a strong Lewis acid (e.g., AlCl3), however the use of such electrolytes requires components of the battery to be composed of materials which can withstand corrosive reactions. One key battery component is the electrode current collector, which offers structural support to the electrode active material, and electrically conducts to complete the circuit which stores and delivers power to a device. Commonly, cheap and structurally stable metals such as Al, Cu, or stainless steel are used as current collectors in rechargeable batteries. To date, inert noble metals such as Platinum (Pt) have been used to demonstrate electrochemical reactions between Mg electrolytes and active materials such as Mo6S8. However commercial realization of rechargeable Mg battery cells requires readily available, cost effective current collectors.
There is a need for improved current collectors for use in batteries having electrolytes containing magnesium ions.